inet/rexec.c

   1 /*
   2  * Copyright (c) 1980, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #if defined(LIBC_SCCS) && !defined(lint)
  31 static char sccsid[] = "@(#)rexec.c     8.1 (Berkeley) 6/4/93";
  32 #endif /* LIBC_SCCS and not lint */
  33
  34 #include <sys/types.h>
  35 #include <sys/socket.h>
  36
  37 #include <netinet/in.h>
  38
  39 #include <alloca.h>
  40 #include <stdio.h>
  41 #include <netdb.h>
  42 #include <errno.h>
  43 #include <string.h>
  44 #include <unistd.h>
  45
  46 int     rexecoptions;
  47
  48 int
  49 rexec(ahost, rport, name, pass, cmd, fd2p)
  50         char **ahost;
  51         int rport;
  52         const char *name, *pass, *cmd;
  53         int *fd2p;
  54 {
  55         struct sockaddr_in sin, sin2, from;
  56         struct hostent hostbuf, *hp;
  57         const char *orig_name = name;
  58         const char *orig_pass = pass;
  59         size_t hstbuflen;
  60         char *hsttmpbuf;
  61         u_short port;
  62         int s, timo = 1, s3;
  63         char c;
  64         int herr;
  65
  66         hstbuflen = 1024;
  67         hsttmpbuf = __alloca (hstbuflen);
  68         while (__gethostbyname_r (*ahost, &hostbuf, hsttmpbuf, hstbuflen,
  69                                   &hp, &herr) != 0
  70                || hp == NULL)
  71           if (herr != NETDB_INTERNAL || errno != ERANGE)
  72             {
  73               __set_h_errno (herr);
  74               herror(*ahost);
  75               return -1;
  76             }
  77           else
  78             {
  79               /* Enlarge the buffer.  */
  80               hstbuflen *= 2;
  81               hsttmpbuf = __alloca (hstbuflen);
  82             }
  83
  84         *ahost = hp->h_name;
  85         ruserpass(hp->h_name, &name, &pass);
  86 retry:
  87         s = __socket(AF_INET, SOCK_STREAM, 0);
  88         if (s < 0) {
  89                 perror("rexec: socket");
  90                 return (-1);
  91         }
  92         sin.sin_family = hp->h_addrtype;
  93         sin.sin_port = rport;
  94         bcopy(hp->h_addr, (caddr_t)&sin.sin_addr, hp->h_length);
  95         if (__connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
  96                 if (errno == ECONNREFUSED && timo <= 16) {
  97                         (void) __close(s);
  98                         __sleep(timo);
  99                         timo *= 2;
 100                         goto retry;
 101                 }
 102                 perror(hp->h_name);
 103                 return (-1);
 104         }
 105         if (fd2p == 0) {
 106                 (void) __write(s, "", 1);
 107                 port = 0;
 108         } else {
 109                 char num[32];
 110                 int s2, sin2len;
 111
 112                 s2 = __socket(AF_INET, SOCK_STREAM, 0);
 113                 if (s2 < 0) {
 114                         (void) __close(s);
 115                         return (-1);
 116                 }
 117                 listen(s2, 1);
 118                 sin2len = sizeof (sin2);
 119                 if (getsockname(s2, (struct sockaddr *)&sin2, &sin2len) < 0 ||
 120                   sin2len != sizeof (sin2)) {
 121                         perror("getsockname");
 122                         (void) __close(s2);
 123                         goto bad;
 124                 }
 125                 port = ntohs((u_short)sin2.sin_port);
 126                 (void) sprintf(num, "%u", port);
 127                 (void) __write(s, num, strlen(num)+1);
 128                 { int len = sizeof (from);
 129                   s3 = accept(s2, (struct sockaddr *)&from, &len);
 130                   __close(s2);
 131                   if (s3 < 0) {
 132                         perror("accept");
 133                         port = 0;
 134                         goto bad;
 135                   }
 136                 }
 137                 *fd2p = s3;
 138         }
 139         (void) __write(s, name, strlen(name) + 1);
 140         /* should public key encypt the password here */
 141         (void) __write(s, pass, strlen(pass) + 1);
 142         (void) __write(s, cmd, strlen(cmd) + 1);
 143
 144         /* We don't need the memory allocated for the name and the password
 145            in ruserpass anymore.  */
 146         if (name != orig_name)
 147           free (name);
 148         if (pass != orig_pass)
 149           free (pass);
 150
 151         if (__read(s, &c, 1) != 1) {
 152                 perror(*ahost);
 153                 goto bad;
 154         }
 155         if (c != 0) {
 156                 while (__read(s, &c, 1) == 1) {
 157                         (void) __write(2, &c, 1);
 158                         if (c == '\n')
 159                                 break;
 160                 }
 161                 goto bad;
 162         }
 163         return (s);
 164 bad:
 165         if (port)
 166                 (void) __close(*fd2p);
 167         (void) __close(s);
 168         return (-1);
 169 }